Subject:Skywatcher StarTravel 80 (ST80)
Date:2005-11-20
Rev:0.1
I have, in the last 3 years gained more and more experience with telescopes and all fields of astronomy. Although i am hardly a professional i do have a very good working knowledge of telescope types and use as well as observing practices. I have been using all the equipment mentioned on this site along with other equipment at star parties. Read on for the first section of my review.
When ordering the ST80 i only went for the OTA(optical tube assembly) because a mount would have been surplus to requirements. In the box i find an OTA, 2 eyepeices, one finder scope(6x30 I think), a camera tripod adaptor, a vixen style dovetail, a 1.6x barlow(1.6x, whats the point in that) and a few other bits of junk! The ep's, the barlow and the finder where offered to anyone who wanted them. To that end there was no assembly required. The scope seemed of the standard Skywatcher build quality with a blue tube and black/dark grey sundries. Altogether, just exactly what i expected, not too much plastic, which is nice!!!
The first time i used this scope was with a canon EOS 300D attached to it so optically i really couldnt tell bad from good. It was also the first time i had tried taking pictures through a scope at prime focus(used to use ep projection with my IXUS). Strangely the pictures of M57 came out really rather well althoug current problems with my PC mean i cant accutally post them on this page! Fear not, i will eventually get round to it!!! After a week or two the sky cleared enough for another observing session! I mounted the scope onto a camera tripod using s single ring because the dual ring system would not allow decent balance, the last thing you want with a wobbly camera tripod!!!
My first target was the Seven Sisters(M45), i wanted to see how well the scope focused on stars and wanted to see the wide field of view these small wide angle scopes produce. M45 fits perfectly in the view with a 32mm Televue. I can just make out the trapezium of stars in the center, they are very small but apparent none the less. The variation in colour of the three stars is surprisingly easy to detect even for such a small apeture scope! Next, on to the Orion nebulae with its ghostly blue and dark areas. As suspected this scope barely make any detail from the nebulae, it is only an 80mm but never the less it still produces some detail the overall shape of the nebulae is clearly visible and one can just about make out the horsey shaped bit in the middle. The next target on the list was Mars, i didnt really hold out much hope for an object as small and bright as this rendering any detail but at 66X(12mm ep + 2x barlow) i could make out a slight pinkish area on the disc... This i found very surprising, such a short focal length but still bing able to pick out surface detail something i did not expect from a tiny F5 scope!!! The clouds started to roll in, as usual, so im giving up now..
Having to shelve the EQ-6 due to living in a first floor flat and having to drive 3 miles to the nearest observing site i decided to get hold of a relativley heavy Alt Az mount. After some deliberation i decided on an AZ3. It is cheap, pretty heavy in contruction and has slow motion controls. It is however, not without its faults. The worst of which is balance. With a short tube scope it is almost impossible to balance whilst using 2 rings. I tried on ring so start with but that led to an uncontrolable wobble even from breath. I gave up trying with a single ring and set the scope back up with 2. The trouble being the bad balance now returned. The balance problem is easily cured by simply tightening the Altitude axis bolt up but that has the secondary effect of making the axis sooooo tight it is very hard to move the scope in Altitude, not somthing i was comfortable with even with such a cheap scope. One evening whilst gazing intently at the EQ-6 i had a flash of inspiration...Counter Weights!!! I sprung into action suddenly realising it was 4AM and my neighbours would not appreciate grinding cutting and welding at that so i slep on it!
The next day i started about assembling a 6mm bright steel bar with some 6mm square section attached at one end to give the fixings something to purchase to. This bolted onto a spare hole in the mounting plate with a single stainless M6 nut washer and nylock. I deliberately left the rod long to start so i could mess around with weight weight and position. I was using tins of air rifle pellets to assess the weight required, 1.5 kilos right under the scope is what was needed. I spent a bit of time googleing for lead shot to fill a bean tin, or weights of the required size. In the end shot would have cost about £5 per pound, the same price as a tin of rifle pellets so i sacificed 3 tins of pellets to balance. The scope now has perfect balance at all but the most extreme elevations and is much easier to use.
Another problem any users of this mount may well have noted is the Altitude slow motion control knob smacking you in the eye when you are tyring to look near the zenith. Again a simple resolve to this problem is to mount the scope with the EP facing away from the Alt slow motion control, trouble with that is actually reaching the slow motion control whilst at the scope!!! To that end i removed the control, detached the handle, cut the wobbly cord off clean at the attachment to mount end and superglued the knob straight onto the attacher. Problem solved, i now no longer get smacked in the face for trying to look up to high!!!